C08G64/00

Processes for recovering and purifying polyhydroxyalkanoates from cell cultures
09683076 · 2017-06-20 · ·

A process for recovering and purifying polyhydroxyalkanoates from a cell culture may include: (a) acidifying the culture to obtain a pH value less than or equal to 6, and submitting the culture to a cell fractionation treatment using high-pressure homogenization at a temperature greater than or equal to 10 C. and less than or equal to 80 C. to obtain a suspension; (b) basifying the suspension to obtain a pH value greater than or equal to 8; (c) diluting the suspension and submitting the diluted PHA suspension to tangential filtration to obtain a concentrated suspension as retentate and an aqueous phase as permeate; (d) submitting the concentrated suspension to bleaching; (e) diluting the suspension after the bleaching and submitting the diluted bleached suspension to tangential filtration to obtain a concentrated bleached suspension as retentate and an aqueous phase as permeate; and/or (f) submitting the concentrated bleached suspension to drying.

Method for preparing branched polycarbonate with continuous two-phase interface phosgene method

The present invention relates to a method for preparing branched polycarbonate with a continuous two-phase interface phosgene method. Firstly, an aqueous solution of alkali metal hydroxide with triphenol and polyphenol dissolved therein reacts with a certain amount of phosgene in the present of inert organic solvent to prepare a prepolymer, and then a coupling reaction is performed among the prepolymer, an aqueous solution of alkali metal hydroxide with bisphenol and phosgene dissolved therein to finally obtain a polycarbonate resin. The method can avoid a cross-linking reaction, reduce the cost and improve the quality of the product, while improving the conversion ratio of the branching agent and the branching degree of the product.

Aromatic polycarbonate resin molding

Provided is an aromatic polycarbonate resin molded body, which is obtained by molding a resin molding material containing an aromatic polycarbonate resin (A), in which: the molded body has a thin-walled portion having a thickness of 0.5 mm or less; the molded body has an o-hydroxyacetophenone content of 1 ppm by mass or less and a nitrogen atom content of 15 ppm or less; and the molded body is free of an absorption maximum in a wavelength range of from 500 nm to 600 nm.

Process or producing polyhydroxyalkanoates from precursors obtained by anaerobic fermentation from fermentable biomass
09650469 · 2017-05-16 · ·

The process for producing polyhydroxyalkanoates or PHA from volatile fatty acid (VFA) molecules, referred to as precursors, produced by anaerobic fermentation from fermentable biomass, characterized in that it comprises at least the following steps: a) extracting the volatile fatty acid (VFA) molecules, without stopping the fermentation, via an extraction means chosen from means that are, at least, insoluble in the fermentation medium, b) collecting, outside the fermentation reactor, the volatile fatty acid (VFA) molecules once they have been extracted, c) synthesizing, by halogenation, using a type of volatile fatty acid (VFA) chosen from the volatile fatty acids collected in step b) and defined according to the desired type of PHA, a given -halo acid, d) synthesizing from this -halo acid molecules of a given -hydroxy acid by reaction with a base, e) polymerizing using the -hydroxy acid obtained a defined polyhydroxyalkanoate (PHA).

PHA compositions comprising PBS and PBSA and methods for their production

Compositions of PHAs with PBS and/or PBSA are described and methods of making the same.

Method for continuously preparing biodegradable aliphatic/aromatic polyester copolymer

Provided is a method of continuous preparation of a biodegradable aliphatic/aromatic polyester copolymer, the method including: performing a first esterification reaction of an aliphatic dihydroxy compound and an aliphatic dicarboxylic acid at a temperature of 185 C. or less; continuously performing a second esterification reaction of a reaction product obtained by the first esterification reaction; obtaining a pre-polymer by continuously performing a first polycondensation reaction of a reaction product obtained by the second esterification reaction; and continuously performing polycondensation reaction of the pre-polymer, wherein an aromatic carboxylic acid is added to a reactor in which the first esterification reaction or the second esterification reaction is performed, to prepare the biodegradable aliphatic/aromatic polyester copolymer. According to the method of continuous preparation of the biodegradable aliphatic/aromatic polyester copolymer as described above, the amount of the aliphatic dihydroxy compound used, which is a starting material, is reduced and accordingly, manufacturing costs are reduced.

Production method for carbonate compound and methacrylate or ester thereof

The present invention relates to a method for producing a carbonate compound and methacrylic acid or an ester thereof, containing a step (a1) of obtaining hexachloroacetone and hydrogen chloride from acetone and chlorine molecule, a step (a2) of obtaining a dialkyl carbonate and chloroform from hexachloroacetone and an alkyl alcohol, a step (b1) of obtaining 1,1,1-trichloro-2-methyl-2-propanol from chloroform and acetone, a step (b2+b3 or b4) of obtaining methacrylic acid or an ester thereof and hydrogen chloride from 1,1,1-trichloro-2-methyl-2-propanol and water or an alcohol, and a step (c1 or c2) of obtaining chlorine molecule by reacting hydrogen chloride with oxygen molecule.

Production method for carbonate compound and methacrylate or ester thereof

The present invention relates to a method for producing a carbonate compound and methacrylic acid or an ester thereof, containing a step (a1) of obtaining hexachloroacetone and hydrogen chloride from acetone and chlorine molecule, a step (a2) of obtaining a dialkyl carbonate and chloroform from hexachloroacetone and an alkyl alcohol, a step (b1) of obtaining 1,1,1-trichloro-2-methyl-2-propanol from chloroform and acetone, a step (b2+b3 or b4) of obtaining methacrylic acid or an ester thereof and hydrogen chloride from 1,1,1-trichloro-2-methyl-2-propanol and water or an alcohol, and a step (c1 or c2) of obtaining chlorine molecule by reacting hydrogen chloride with oxygen molecule.

Process for the purification of polycarbonate

In an embodiment, a process of purifying a polycarbonate from an interfacial polymerization product mixture comprising an aqueous phase and an organic phase comprising a first organic solvent, the polycarbonate, a catalyst, and ions, the process comprises: separating the aqueous phase and the organic phase to form a separated aqueous feed stream and a separated organic stream; extracting the catalyst and the ions from the separated organic stream to form a purified polycarbonate stream and an extracted aqueous feed stream, wherein at least one of the separated aqueous feed stream and the extracted aqueous feed stream comprise an organic portion and an aqueous portion; purifying an aqueous stream comprising one or both of the separated aqueous feed stream and the extracted aqueous feed stream by adjusting a viscosity of the organic portion to be less than or equal to 40 centipoise by adding a second organic solvent to the aqueous stream to form a combined stream; optionally, adjusting a ratio of the aqueous portion to the organic portion to 1.0 to 20.0 by adding an aqueous solution to the aqueous stream; and separating the combined stream to form a purified aqueous stream, wherein less than or equal to 3 vol % of the purified aqueous stream is the organic portion.

Thermal enhancement of the purification process for interfacial polycarbonate and copolymer polycarbonates

In an embodiment, a process of purifying a polycarbonate comprises: polymerizing a dihydroxy compound and a carbonate source via an interfacial reaction in the presence of a catalyst to form a product mixture comprising an aqueous phase and an organic phase, wherein the organic phase comprises the polycarbonate, the catalyst, ions, and a solvent having a boiling point T.sub.b; heating the product mixture to greater than or equal to T.sub.b; separating the aqueous phase and the organic phase at a temperature greater than or equal to T.sub.b to form a separated organic phase and a separated aqueous phase; extracting the catalyst from the separated organic phase; and extracting the ions from the separated organic phase; wherein if a centrifuge is used in the extracting of the catalyst, the extracting of the ions, or both, the process further comprises cooling a stream entering the centrifuge to less than T.sub.b.